In recent years, a virtualization technology that operates virtual machines in physical servers is used. For example, in each data center, an environment in which virtual machines are operated in multiple physical servers by using virtualization software is increased. The virtualization software has the function of moving a virtual machine running on a physical server to another physical server. This moving of a virtual machine is also referred to as “migration”.
As a technology for distributing the load on the multiple physical servers in which the virtual machines are running, there is a method of migrating a virtual machine from, for example, a physical server to which a high load is applied to a physical server to which a low load is applied. Furthermore, as a technology for distributing the load, there is a proposed technology that uses, as a condition, at least one of the electrical power consumption and the amount of I/O; that calculates a cost for each pattern for multiple calculating processes that are distributed to multiple virtual machines; and that selects a pattern for the lowest cost.
Patent Literature 1: Japanese Laid-open Patent Publication No. 2010-218307
The conventional technology can distribute the load such that the load is not applied to a specific physical server; however, there is a problem in that, when virtual machines communicate and the communication distance between the virtual machines is great, the traffic in a network increases and thus a delay may possibly occur in the network.